The present invention relates to a defect data analyzing method for analyzing defect distribution states from the defect data detected by inspection apparatus in a semiconductor device manufacturing process in which circuit patterns are formed on a semiconductor substrate.
In the semiconductor device manufacturing process in which circuit patterns are formed on a semiconductor substrate (hereafter, referred to as semiconductor substrate production process), pattern defect inspection or foreign matter inspection is executed after each process, and the inspection results are analyzed, in order to improve and stabilize the yield. In other words, the operator observes the detected defects on an optical microscope or scanning electron microscope to know the kinds of the defects and identify the causes of the defects. This operation is called review. A method for making effective review is disclosed in JP-A-10-214866. In this method, the region in which defects are concentrated is recognized as a cluster from the defect distribution, and a review point is selected on the basis of the area and shape of the cluster.
Another method for analyzing the inspection result is proposed to try to estimate the cause of defects in apparatus or process from the analysis of defect distribution states. JP-A-6-61314 describes that wafers are grouped according to the state in which the defect map has clusters, and it is decided if they have similarities to known patterns, thereby identifying the cause of defects. In addition, U.S. Pat. No. 5,982,920 describes that each defect is classified as one of minute cluster, linear cluster, indefinite-form cluster and global type other than cluster, and related to a cause of defect.